3 files changed, 102 insertions, 2 deletions

diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index b0811253d101..c8712942002f 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -188,12 +188,16 @@ void dsa_port_disable_rt(struct dsa_port *dp);
 void dsa_port_disable(struct dsa_port *dp);
 int dsa_port_bridge_join(struct dsa_port *dp, struct net_device *br,
 			 struct netlink_ext_ack *extack);
+int dsa_port_pre_bridge_leave(struct dsa_port *dp, struct net_device *br,
+			      struct netlink_ext_ack *extack);
 void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br);
 int dsa_port_lag_change(struct dsa_port *dp,
 			struct netdev_lag_lower_state_info *linfo);
 int dsa_port_lag_join(struct dsa_port *dp, struct net_device *lag_dev,
 		      struct netdev_lag_upper_info *uinfo,
 		      struct netlink_ext_ack *extack);
+int dsa_port_pre_lag_leave(struct dsa_port *dp, struct net_device *lag_dev,
+			   struct netlink_ext_ack *extack);
 void dsa_port_lag_leave(struct dsa_port *dp, struct net_device *lag_dev);
 int dsa_port_vlan_filtering(struct dsa_port *dp, bool vlan_filtering,
 			    struct netlink_ext_ack *extack);
diff --git a/net/dsa/port.c b/net/dsa/port.c
index 4e58d07ececd..46089dd2b2ec 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -212,7 +212,33 @@ static int dsa_port_switchdev_sync(struct dsa_port *dp,
 	return 0;
 }
 
-static void dsa_port_switchdev_unsync(struct dsa_port *dp)
+static int dsa_port_switchdev_unsync_objs(struct dsa_port *dp,
+					  struct net_device *br,
+					  struct netlink_ext_ack *extack)
+{
+	struct net_device *brport_dev = dsa_port_to_bridge_port(dp);
+	int err;
+
+	/* Delete the switchdev objects left on this port */
+	err = br_mdb_replay(br, brport_dev, dp, false,
+			    &dsa_slave_switchdev_blocking_notifier, extack);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	err = br_fdb_replay(br, brport_dev, dp, false,
+			    &dsa_slave_switchdev_notifier);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	err = br_vlan_replay(br, brport_dev, dp, false,
+			     &dsa_slave_switchdev_blocking_notifier, extack);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	return 0;
+}
+
+static void dsa_port_switchdev_unsync_attrs(struct dsa_port *dp)
 {
 	/* Configure the port for standalone mode (no address learning,
 	 * flood everything).
@@ -278,6 +304,12 @@ out_rollback:
 	return err;
 }
 
+int dsa_port_pre_bridge_leave(struct dsa_port *dp, struct net_device *br,
+			      struct netlink_ext_ack *extack)
+{
+	return dsa_port_switchdev_unsync_objs(dp, br, extack);
+}
+
 void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br)
 {
 	struct dsa_notifier_bridge_info info = {
@@ -297,7 +329,7 @@ void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br)
 	if (err)
 		pr_err("DSA: failed to notify DSA_NOTIFIER_BRIDGE_LEAVE\n");
 
-	dsa_port_switchdev_unsync(dp);
+	dsa_port_switchdev_unsync_attrs(dp);
 }
 
 int dsa_port_lag_change(struct dsa_port *dp,
@@ -365,6 +397,15 @@ err_lag_join:
 	return err;
 }
 
+int dsa_port_pre_lag_leave(struct dsa_port *dp, struct net_device *lag,
+			   struct netlink_ext_ack *extack)
+{
+	if (dp->bridge_dev)
+		return dsa_port_pre_bridge_leave(dp, dp->bridge_dev, extack);
+
+	return 0;
+}
+
 void dsa_port_lag_leave(struct dsa_port *dp, struct net_device *lag)
 {
 	struct dsa_notifier_lag_info info = {
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 20d8466d78f2..898ed9cf756f 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -2077,6 +2077,26 @@ static int dsa_slave_changeupper(struct net_device *dev,
 	return err;
 }
 
+static int dsa_slave_prechangeupper(struct net_device *dev,
+				    struct netdev_notifier_changeupper_info *info)
+{
+	struct dsa_port *dp = dsa_slave_to_port(dev);
+	struct netlink_ext_ack *extack;
+	int err = 0;
+
+	extack = netdev_notifier_info_to_extack(&info->info);
+
+	if (netif_is_bridge_master(info->upper_dev) && !info->linking)
+		err = dsa_port_pre_bridge_leave(dp, info->upper_dev, extack);
+	else if (netif_is_lag_master(info->upper_dev) && !info->linking)
+		err = dsa_port_pre_lag_leave(dp, info->upper_dev, extack);
+	/* dsa_port_pre_hsr_leave is not yet necessary since hsr cannot be
+	 * meaningfully enslaved to a bridge yet
+	 */
+
+	return notifier_from_errno(err);
+}
+
 static int
 dsa_slave_lag_changeupper(struct net_device *dev,
 			  struct netdev_notifier_changeupper_info *info)
@@ -2103,6 +2123,35 @@ dsa_slave_lag_changeupper(struct net_device *dev,
 	return err;
 }
 
+/* Same as dsa_slave_lag_changeupper() except that it calls
+ * dsa_slave_prechangeupper()
+ */
+static int
+dsa_slave_lag_prechangeupper(struct net_device *dev,
+			     struct netdev_notifier_changeupper_info *info)
+{
+	struct net_device *lower;
+	struct list_head *iter;
+	int err = NOTIFY_DONE;
+	struct dsa_port *dp;
+
+	netdev_for_each_lower_dev(dev, lower, iter) {
+		if (!dsa_slave_dev_check(lower))
+			continue;
+
+		dp = dsa_slave_to_port(lower);
+		if (!dp->lag_dev)
+			/* Software LAG */
+			continue;
+
+		err = dsa_slave_prechangeupper(lower, info);
+		if (notifier_to_errno(err))
+			break;
+	}
+
+	return err;
+}
+
 static int
 dsa_prevent_bridging_8021q_upper(struct net_device *dev,
 				 struct netdev_notifier_changeupper_info *info)
@@ -2206,6 +2255,12 @@ static int dsa_slave_netdevice_event(struct notifier_block *nb,
 		if (err != NOTIFY_DONE)
 			return err;
 
+		if (dsa_slave_dev_check(dev))
+			return dsa_slave_prechangeupper(dev, ptr);
+
+		if (netif_is_lag_master(dev))
+			return dsa_slave_lag_prechangeupper(dev, ptr);
+
 		break;
 	}
 	case NETDEV_CHANGEUPPER: